the best way i have found to get you guild level up is arena.
You could just invite people to you new guild to help level it up. just send them a wispier " Hey i was wondering if you were interested in joining a guild? find people using the "WHO" tab start with deathknights 55-59
60% said yes to joining mine. once you get to level 5 you get the revenue guild perk, free gold then.
The only downside of having you own guild is that if you want the guild rewards you might have to get friends or do them yourself.
So join a level 25 guild with everything unlocked, Get to Exalted then buy all the stuff your toons need and then create your guild!